Why do we put oxygen in aluminum cylinders?

[Wookie]

Usually it's me.....

 

[cathal]

Anorak; the word I was looking for to describe the discussion of potential explosions using 02 in Al tanks.Much more likely to die breathing the wrong mix at depth.

I know sad really, but when your stuck behind a desk it does create some entertainment

 

[nadwidny]

What I read somewhere years ago and cannot find now was that in the aftermath of the Apollo I fire that killed three astronauts, including most famously Gus Grissom, NASA experiments indicated that atmospheres with 50% O2 or more behaved about the same in terms of danger, but that danger dropped quickly at lower concentrations.

I dug around some old papers and found a copy of this-. "Component Testing and Clean Verification of SCUBA Equipment for the NASA JSC Neutral Bouyancy Laboratory" December 22, 1997. Not done because of the Apollo I fire but because the divers at the NBL were breathing 21-49% O2 mixtures and NASA wanted to make sure things weren't going to go south with the divers' regs.

 

[boulderjohn]

I dug around some old papers and found a copy of this-. "Component Testing and Clean Verification of SCUBA Equipment for the NASA JSC Neutral Bouyancy Laboratory" December 22, 1997. Not done because of the Apollo I fire but because the divers at the NBL were breathing 21-49% O2 mixtures and NASA wanted to make sure things weren't going to go south with the divers' regs.

That's probably what I was thinking of.

 

[TrimixToo]

I haven't slung an LP50 so i can't compare it to anything in the water. AL40s sling awesome, you barely know they're there. I've considered trying an LP72 as I've heard a few old timers swear they make awesome deco bottles, but haven't needed that size O2 bottle too often.

I use LP72s routinely, and own a bunch of them. They are great shallow-water doubles and deco bottles for deep diving. After Dive 2, there's usually enough left over to buddy breathe or hand someone who's run out of deco gas so you can both get out of the water sooner. You can usually pick them up dirt cheap; I've paid as little as $50 for two. A hydro, tumble, and cleaning later, they are ready to go. I even have some with ICC numbers on them!

As is true of AL80s, there are 72s and there are 72s. Some are floaty at the bottom, others not. They have different buoyancy when full and when empty, too. They are smaller than AL80s, which is nice. They are lower pressure, which makes me less nervous when doing O2 fills, which is also nice. On days I don't use 72s for deco, I use LP45s.

Anyone who wants to try one out in the Dutchess County NY area is welcome to try one.

John